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burch
09-26-2009, 10:02 AM
I`m using the simple method of casting with a pot and ladle. I`ve been noticing my bullets are coming out sweeter when the lead is about gone in the pot. I`m wondering if this is a Temp issue. I don`t use a thermometer but was wondering if I should start using one. Also, is their any kind of reference on what temps I should be casting at. All my casting is done for pistol bullets running around 750 - 850 FPS.

Burch

rob45
09-26-2009, 12:40 PM
In your case, I would say that your particular combination likes it hot. You did not mention what volume of lead you're using per session and what conditions your mold is operating under (how hot the mold is.)

Are you preheating the mold? If you're only casting a few pounds at a time and not preheating the mold, the mold may not be hot enough until you get halfway through the session. Same concept applies to your ladle; it needs to be hot and also kept hot. But it sounds like the condition you are observing also relates to the melt itself.

The more volume of lead in a pot, the more BTU's required to maintain a molten state. So when you're starting with a full pot you have your burner (dial or whatever) adjusted to keep it melted. As the lead level drops, there is less material to absorb the heat, so the lead that is still in there is now hotter- remember, your burner is still producing the same amount of heat but now there is less lead to absorb that heat.

I would definitely invest in a thermometer and use it. Keep detailed records on each casting session the same as you would any other step of the reloading process. Doing so helps you sort out any problems, and also helps you identify and replicate the ideal methods/conditions when you do find the sweet spot.

As far as temps go, there is no alloy that we use for bullet casting that requires temps above 750. Pure lead is the one that needs to be the hottest, and some people cast as high as 800 or even more with it, but I have never had to do that. Anything with tin in it will lower the need for high temp. Most of the stuff we use does well around 650 unless it is pure lead. Someone casting with a ladle usually needs to run hotter than someone with a bottom-pour simply due to the fact that the lead is away from the heat source a little bit longer before it goes into the mold. Experiment with YOUR particular combination and see what works best for you. That is why you need a thermometer and take notes when you use it.

burch
09-26-2009, 12:51 PM
In your case, I would say that your particular combination likes it hot. You did not mention what volume of lead you're using per session and what conditions your mold is operating under (how hot the mold is.)

Are you preheating the mold? If you're only casting a few pounds at a time and not preheating the mold, the mold may not be hot enough until you get halfway through the session. Same concept applies to your ladle; it needs to be hot and also kept hot. But it sounds like the condition you are observing also relates to the melt itself.

The more volume of lead in a pot, the more BTU's required to maintain a molten state. So when you're starting with a full pot you have your burner (dial or whatever) adjusted to keep it melted. As the lead level drops, there is less material to absorb the heat, so the lead that is still in there is now hotter- remember, your burner is still producing the same amount of heat but now there is less lead to absorb that heat.

I would definitely invest in a thermometer and use it. Keep detailed records on each casting session the same as you would any other step of the reloading process. Doing so helps you sort out any problems, and also helps you identify and replicate the ideal methods/conditions when you do find the sweet spot.

As far as temps go, there is no alloy that we use for bullet casting that requires temps above 750. Pure lead is the one that needs to be the hottest, and some people cast as high as 800 or even more with it, but I have never had to do that. Anything with tin in it will lower the need for high temp. Most of the stuff we use does well around 650 unless it is pure lead. Someone casting with a ladle usually needs to run hotter than someone with a bottom-pour simply due to the fact that the lead is away from the heat source a little bit longer before it goes into the mold. Experiment with YOUR particular combination and see what works best for you. That is why you need a thermometer and take notes when you use it.

Great info and thank you Sir. I`ll order a thermometer. Any help in selecting a decent one ?

DaveInFloweryBranchGA
09-26-2009, 01:20 PM
Good thermometer can be had at antimonyman.com

rob45
09-26-2009, 01:40 PM
Good thermometer can be had at antimonyman.com

+1 on that recommendation. Not only does Bill carry quality stuff, but he is also a wonderful source of information, both credible and reliable.

thebigmac
09-26-2009, 03:08 PM
www.antimonyman.com does not come up???????????? Mac

burch
09-26-2009, 03:51 PM
I got to the web site but i`m a little tight on funds for a $50 thermometer. Has anyone tried the Lyman.

AJ Peacock
09-26-2009, 03:59 PM
I got to the web site but i`m a little tight on funds for a $50 thermometer. Has anyone tried the Lyman.

This one has been recommended a few times on this site.
http://www.teltru.com/p-272-big-green-egg-grill-dome-kamado-replacement-thermometer-lt225r-2001000-degrees-f.aspx

I ordered one and haven't had a chance to use it yet. It appears to be high quality and exactly what I needed.

Hope this helps,
AJ

rob45
09-26-2009, 06:08 PM
www.antimonyman.com does not come up???????????? Mac

Try this one.

http://www.theantimonyman.com/

burch
09-26-2009, 07:54 PM
This one has been recommended a few times on this site.
http://www.teltru.com/p-272-big-green-egg-grill-dome-kamado-replacement-thermometer-lt225r-2001000-degrees-f.aspx

I ordered one and haven't had a chance to use it yet. It appears to be high quality and exactly what I needed.

Hope this helps,
AJ

Now that`s more to my likin`[smilie=s:

RayinNH
09-26-2009, 08:05 PM
I`ve been noticing my bullets are coming out sweeter when the lead is about gone in the pot.

Burch, you probably shouldn't be tasting these :-D...Ray

burch
09-26-2009, 09:01 PM
Burch, you probably shouldn't be tasting these :-D...Ray


:lol:

Bret4207
09-27-2009, 10:31 AM
There are two temps to be concerned with- pot temp and mould temp. IMO and IME pot temp is the less important of the 2 once you get up to a usable mould temp. I used to be one of the "cast, cut the sprue, dump the boolit and look at it/them, roll them around and check fill out, check the mould for stray flecks of lead, look at the boolits again, take a sip of coffee and make another pour". Doesn't work very well and I had to run my pot very hot to get a halfway decent boolit. Now I preheat the mould and cast as fast as I can till the boolits start frosting. Once I get a slight frost I back down my speed a little bit and just cast, cast, cast. The mould temp is what determines your boolit fillout-assuming your alloy is coming out of the pot hot enough. Last casting session I was making perfect boolits from 3 different moulds at just under 700 degrees from a SAECO bp. I think I could have gone lower. With some moulds no matter how fast you cast you have to up the pot temp to raise the mould heat, and I agree with the other poster that with my beloved ladle you need to run a bit hotter. But- with my ladle I tend to leave a much larger sprue and it helps keep the mould hot.

Its all part of the "art" end of casting. If you want to continue with the ladle, and I used one for 30+ years, then I suggest getting a LARGE pot. I use a 12 cup stainless measuring cup that holds way over 20lbs, probably closer to 30 lbs and a simple open coil hot plate. I can hold temp with in 15 degrees with that set up and the stainless results in a lot less crap in my pot.